Could a Chinese herb be natural Viagra?
“We have not yet conducted in-vivo experiments on animals, so we still have a lot of work to do. We want to test the molecule in vivo (on animals), as this will help us find out if it will really work on humans, “said Mario Del Ali, the study’s lead researcher in the pharmacognosy laboratory at the University of Milan. “At this stage of the study, we can’t say for sure that the molecule we synthesized will cause fewer side effects than those of Viagra. However, this derivative appears to be more selective than Viagra (according to laboratory tests) because it targets more precisely the enzyme involved in blood flow to the penis. ”
Viagra (sildenafil) is one of the medications prescribed for erection problems (erectile dysfunction). The condition affects approximately 18 million men in the United States. Viagra, like other medications of that type, can cause side effects such as heart pain, stomach problems and vision problems.
Horny goat weed (the herb is also known as “naughty goat”, “horny goat”, “spoiled goat”), harvested mainly in southern China, has a long history as an aphrodisiac.
As part of a new screening program aimed at finding alternatives to Viagra, the study’s authors analyzed a number of herbal extracts long used for male impotence. Ferula hermonis, known as Lebanese Viagra, Cinnamomum cassia or Chinese cinnamon, as well as Epimedium brevicornum, known as “horned goat grass” or “spoiled goat”, were studied. All three of these extracts are known to improve sexual performance.
The main active ingredient in all three extracts was tested against an enzyme called phosphodiesterase-5A1 (PDE5A1), which regulates the blood supply to the penis. Suppression of this enzyme provides greater blood flow to the penis, leading to an erection.
Icariin, the main constituent of horny goat grass, inhibits PDE5A1 to a much greater extent than the other two components tested.
“What’s new in our study is the new molecule we synthesized from icarin,” says Del Ali. “It is extracted by chemical modification of the structure of icarin, which is an active ingredient purified from E. brevicornum (horny goat grass). The mechanism by which the molecule we discovered may be effective in humans is the suppression of phosphodiesterase 5 (PDE 5) in the corpus cavernosum (erectile tissue of the penis), which is the mechanism by which Viagra works. This is an in-vitro study. It may be considered as a preliminary clinical trial. ”
Source: Mario Dell’Agli, Ph.D., laboratory of pharmacognosy, University of Milan, Italy; Oct. 24, 2008, Journal of Natural Products
Author: Amanda Gardner, HealthDay reporter
